Lighting the Path: A Sustainable Catalyst Free Approach Toward Trifluoromethylation of Indoles

In this study, we report an innovative development of a visible light-induced synthesis of trifluoromethyl indoles. This novel methodology not only obviates the need for traditional catalysts but also harnesses the energy of photons to selectively introduce trifluoromethyl groups into indole substrates. Leveraging the inexpensive, easily handled, and non-toxic Langlois reagent (CF₃SO₂Na) as the CF₃ source, in conjunction with visible light and tert-butyl hydrogen peroxide (TBHP), facilitates the direct C─H trifluoromethylation of indoles. The mechanistic pathway of the reaction is predicted with the help of density functional theory (DFT) calculations at the (U)B3LYP/6–31++G(d,p)/SMD/acetonitrile level of theory.